Upright-piano action



(No Model.)

P. M. LAWSON.

UPRIGHT PIANO ACTION.

No. 350,000. Patented Sept. 28, 1886.

. K .if i E [Q lUNrrnD Snrirri-:s

PATENT Ortner-a FRED MITCHELL LAVSON, OF CAMBRIDGE, MASSACHUSETTS.

UPRlGHT-PIANO ACTlON.

S'SCIFICATON forming part oi Letters Patent No. 350,006, dated September 223, 1886,

(No modul.)

To all whom, it may concern.-

Be it known that'il, Fiano lllrronnrir. LawsON, ol' Cambridge, in the county of Middlesex, ot' the Commonwealth of Massachusetts, have invented a new and useful. Improvement. in Ilpright-liano-Forte Actions; and I do hereby declare the same to be described in the i'ollowing specification, and represented in the accompanying drawing, which is a side elcvation ol' a key and its action provided with my invention, the nai ure of which is defined in the claim hereinafter presented.

ln suoli drawing, A denotes the key, 3, the hammer; G, thev jack; D, the jack-supporting lever, and ll the said jack-lever elevated. The lever D extends underand is iulcrumed to a stationary bar or rail, F, in front of which is a movable bar or rail, Cf, to which the hammer is hinged. The said bar G- projects from the lower arm oi' a lever, H, to whose upper arm the back-rest lY oi` the hammer is lixed. The fnlcrum ol' the lever Il is represented at a. The string is shown at J, and its damper at K, such damper being i'ulcrnmed to the bar F, and has a back-stop, L, as represented. A pin, Z), extending upward from and :fastened on the rear arm of the jack-supporting lever l'),is carried against the tail'of the damper during an upward vertical movement of thejacksupporting lever and throws the damper oil` the string.. rllhe back-catch of the hammer is shown at M as supported by a wire, b', projecting upward from the front arm of thej acklever l). llo another wire, c, extending up` ward from such i'rout arm, and to the tailblock d ol' the hammer, the hammer-retractor c is fastened. The tripping-button ol' thejack is shown atf as having its shank g screwed through a bar or rail, 71, supported by a bent arm, fi, proiecting, as represented, from arockshaft, Lr, journaled at one end in a stationary strut, my. From this rock-shaft astifl1 wire, n, extends upward through a slide, o, arranged to move on the wire lengthwise thereof and held thereto by a set-screw, p, screwed into the said slide and against the wire. To this slide and the upper arm ofthe lever I-I a connecting-rml, r, is jointed, the same being to cause the lever I-I, while being moved, to advance thehammer and vits baek-resttoward the string to turn the rock-shalt, so as to depress the tripping-button fnearer to the shorter arm or projection s of the jack.

Before my invention it has been customary, by means ot' a pedal, to move the hammer and its back-rest toward the string, in order to prod nce a short movement ol' the hammer by the key. This, however, carried the jack so far below the tail-block of the hammer as to require a considerable movement of the key before thejaok could be forced up to the said` block. This rendered rapid movements of the hammer by the key more or less difficult; but with my improvements the hammerrail is movable with the hammer and its back-rest, the said hammer-rail, while the back-rest is advancing, being moved in a direction away from the rail or bar, to which the damper and jack-supporting lever are hinged. The fulcruni ot the lever that carries the back-rest and the hammer-rail is on a level or in line with the jack-bearing of thehammer. Consequently while the hammer and its back-rest are moved forward toward the string, the said bearing or part of the tail of the hammer, against which the upper end of the jack works maintains its position, notwithstanding the hammer-sustaining rail is at the same time in movement away from the damper and ,jacklever rail. 1While the back-rest and hammer are beingmoved forward toward the string, the jack-operating button-supporting rail is being depressed toward the part s ol thejaclt that is directly under it, from which it will be seen that very little movement of the key will suffice to vibrate the hammer rapidly to the string. Therefore, with my invention, a performer does not have to move a key nearly so far to effect a movement of the hammer to the string when the hammer and its back-rest are in an advanced position, as would be the case were the hammer pivoted to a stationary rail as heretofore.

Vith my improvement the jack maintains its position relatively to the tail-block of the hammer, whatever may be the distance of the hammer from the string, and thus in depressing the key the performer has the jack close up to the tail-block, and does nothave to force the jack upward a distance, in order for it to act on the tail-block.

I claim- IOO The back-restI and the hammer-supportingv mechanism being the rock-shaft 7c, bent arm to rail G, arranged with and fastened to opposite fi, wire n, adjustable slide o, and the rod r, arms of a lever, H, as set forth, having its fulconnecting such slide with the upper arm of crum level 01' essentially in line with the jaekthe back-rest lever H, all being essentially as 5' bearings of the hammers, in combination with l represented.

thejaek-button-supportingrailh,having meeh- I FRED MITCHELL LAVSON.

anism, substantially as described, for moving Witnesses: it downward toward thejaek during the ad- R. H. EDDY, vance of the back-rest of the ha1nmer,such R. B. TORREY. 

